ttrss/classes/config.php

<?php
class Config {
	private const _ENVVAR_PREFIX = "TTRSS_";

	const T_BOOL = 1;
	const T_STRING = 2;
	const T_INT = 3;

	// override defaults, defined below in _DEFAULTS[], via environment: DB_TYPE becomes TTRSS_DB_TYPE, etc

	const DB_TYPE = "DB_TYPE";
	const DB_HOST = "DB_HOST";
	const DB_USER = "DB_USER";
	const DB_NAME = "DB_NAME";
	const DB_PASS = "DB_PASS";
	const DB_PORT = "DB_PORT";
	const MYSQL_CHARSET = "MYSQL_CHARSET";
	const SELF_URL_PATH = "SELF_URL_PATH";
	const SINGLE_USER_MODE = "SINGLE_USER_MODE";
	const SIMPLE_UPDATE_MODE = "SIMPLE_UPDATE_MODE";
	const PHP_EXECUTABLE = "PHP_EXECUTABLE";
	const LOCK_DIRECTORY = "LOCK_DIRECTORY";
	const CACHE_DIR = "CACHE_DIR";
	const ICONS_DIR = "ICONS_DIR";
	const ICONS_URL = "ICONS_URL";
	const AUTH_AUTO_CREATE = "AUTH_AUTO_CREATE";
	const AUTH_AUTO_LOGIN = "AUTH_AUTO_LOGIN";
	const FORCE_ARTICLE_PURGE = "FORCE_ARTICLE_PURGE";
	const SESSION_COOKIE_LIFETIME = "SESSION_COOKIE_LIFETIME";
	const SMTP_FROM_NAME = "SMTP_FROM_NAME";
	const SMTP_FROM_ADDRESS = "SMTP_FROM_ADDRESS";
	const DIGEST_SUBJECT = "DIGEST_SUBJECT";
	const CHECK_FOR_UPDATES = "CHECK_FOR_UPDATES";
	const PLUGINS = "PLUGINS";
	const LOG_DESTINATION = "LOG_DESTINATION";
	const LOCAL_OVERRIDE_STYLESHEET = "LOCAL_OVERRIDE_STYLESHEET";
	const DAEMON_MAX_CHILD_RUNTIME = "DAEMON_MAX_CHILD_RUNTIME";
	const DAEMON_MAX_JOBS = "DAEMON_MAX_JOBS";
	const FEED_FETCH_TIMEOUT = "FEED_FETCH_TIMEOUT";
	const FEED_FETCH_NO_CACHE_TIMEOUT = "FEED_FETCH_NO_CACHE_TIMEOUT";
	const FILE_FETCH_TIMEOUT = "FILE_FETCH_TIMEOUT";
	const FILE_FETCH_CONNECT_TIMEOUT = "FILE_FETCH_CONNECT_TIMEOUT";
	const DAEMON_UPDATE_LOGIN_LIMIT = "DAEMON_UPDATE_LOGIN_LIMIT";
	const DAEMON_FEED_LIMIT = "DAEMON_FEED_LIMIT";
	const DAEMON_SLEEP_INTERVAL = "DAEMON_SLEEP_INTERVAL";
	const MAX_CACHE_FILE_SIZE = "MAX_CACHE_FILE_SIZE";
	const MAX_DOWNLOAD_FILE_SIZE = "MAX_DOWNLOAD_FILE_SIZE";
	const MAX_FAVICON_FILE_SIZE = "MAX_FAVICON_FILE_SIZE";
	const CACHE_MAX_DAYS = "CACHE_MAX_DAYS";
	const MAX_CONDITIONAL_INTERVAL = "MAX_CONDITIONAL_INTERVAL";
	const DAEMON_UNSUCCESSFUL_DAYS_LIMIT = "DAEMON_UNSUCCESSFUL_DAYS_LIMIT";
	const LOG_SENT_MAIL = "LOG_SENT_MAIL";
	const HTTP_PROXY = "HTTP_PROXY";
	const FORBID_PASSWORD_CHANGES = "FORBID_PASSWORD_CHANGES";
	const SESSION_NAME = "SESSION_NAME";

	private const _DEFAULTS = [
		Config::DB_TYPE => [ "pgsql", 									Config::T_STRING ],
		Config::DB_HOST => [ "db", 										Config::T_STRING ],
		Config::DB_USER => [ "",											Config::T_STRING ],
		Config::DB_NAME => [ "", 											Config::T_STRING ],
		Config::DB_PASS => [ "", 											Config::T_STRING ],
		Config::DB_PORT => [ "5432",										Config::T_STRING ],
		Config::MYSQL_CHARSET => [ "UTF8",								Config::T_STRING ],
		Config::SELF_URL_PATH => [ "",									Config::T_STRING ],
		Config::SINGLE_USER_MODE => [ "",								Config::T_BOOL ],
		Config::SIMPLE_UPDATE_MODE => [ "",								Config::T_BOOL ],
		Config::PHP_EXECUTABLE => [ "/usr/bin/php",					Config::T_STRING ],
		Config::LOCK_DIRECTORY => [ "lock",								Config::T_STRING ],
		Config::CACHE_DIR => [ "cache",									Config::T_STRING ],
		Config::ICONS_DIR => [ "feed-icons",							Config::T_STRING ],
		Config::ICONS_URL => [ "feed-icons",							Config::T_STRING ],
		Config::AUTH_AUTO_CREATE => [ "true",							Config::T_BOOL ],
		Config::AUTH_AUTO_LOGIN => [ "true",							Config::T_BOOL ],
		Config::FORCE_ARTICLE_PURGE => [ 0,								Config::T_INT ],
		Config::SESSION_COOKIE_LIFETIME => [ 86400,					Config::T_INT ],
		Config::SMTP_FROM_NAME => [ "Tiny Tiny RSS",					Config::T_STRING ],
		Config::SMTP_FROM_ADDRESS => [ "noreply@localhost",		Config::T_STRING ],
		Config::DIGEST_SUBJECT => [ "[tt-rss] New headlines for last 24 hours",
																					Config::T_STRING ],
		Config::CHECK_FOR_UPDATES => [ "true",							Config::T_BOOL ],
		Config::PLUGINS => [ "auth_internal",							Config::T_STRING ],
		Config::LOG_DESTINATION => [ "sql",								Config::T_STRING ],
		Config::LOCAL_OVERRIDE_STYLESHEET => [ "local-overrides.css",
																					Config::T_STRING ],
		Config::DAEMON_MAX_CHILD_RUNTIME => [ 1800,					Config::T_STRING ],
		Config::DAEMON_MAX_JOBS => [ 2,									Config::T_INT ],
		Config::FEED_FETCH_TIMEOUT => [ 45,								Config::T_INT ],
		Config::FEED_FETCH_NO_CACHE_TIMEOUT => [ 15,					Config::T_INT ],
		Config::FILE_FETCH_TIMEOUT => [ 45,								Config::T_INT ],
		Config::FILE_FETCH_CONNECT_TIMEOUT => [ 15,					Config::T_INT ],
		Config::DAEMON_UPDATE_LOGIN_LIMIT => [ 30,					Config::T_INT ],
		Config::DAEMON_FEED_LIMIT => [ 500,								Config::T_INT ],
		Config::DAEMON_SLEEP_INTERVAL => [ 120,						Config::T_INT ],
		Config::MAX_CACHE_FILE_SIZE => [ 64*1024*1024,				Config::T_INT ],
		Config::MAX_DOWNLOAD_FILE_SIZE => [ 16*1024*1024,			Config::T_INT ],
		Config::MAX_FAVICON_FILE_SIZE => [ 1*1024*1024,				Config::T_INT ],
		Config::CACHE_MAX_DAYS => [ 7,									Config::T_INT ],
		Config::MAX_CONDITIONAL_INTERVAL => [ 3600*12,				Config::T_INT ],
		Config::DAEMON_UNSUCCESSFUL_DAYS_LIMIT => [ 30,				Config::T_INT ],
		Config::LOG_SENT_MAIL => [ "",									Config::T_BOOL ],
		Config::HTTP_PROXY => [ "",										Config::T_STRING ],
		Config::FORBID_PASSWORD_CHANGES => [ "",						Config::T_BOOL ],
		Config::SESSION_NAME => [ "ttrss_sid",							Config::T_STRING ],
	];

	private static $instance;

	private $params = [];
	private $schema_version = null;
	private $version = [];

	public static function get_instance() : Config {
		if (self::$instance == null)
			self::$instance = new self();

		return self::$instance;
	}

	private function __clone() {
		//
	}

	function __construct() {
		$ref = new ReflectionClass(get_class($this));

		foreach ($ref->getConstants() as $const => $cvalue) {
			if (isset($this::_DEFAULTS[$const])) {
				$override = getenv($this::_ENVVAR_PREFIX . $const);

				list ($defval, $deftype) = $this::_DEFAULTS[$const];

				$this->params[$cvalue] = [ self::cast_to(!empty($override) ? $override : $defval, $deftype), $deftype ];
			}
		}
	}

	/* package maintainers who don't use git: if version_static.txt exists in tt-rss root
		directory, its contents are displayed instead of git commit-based version, this could be generated
		based on source git tree commit used when creating the package */

	static function get_version(bool $as_string = true) {
		return self::get_instance()->_get_version($as_string);
	}

	private function _get_version(bool $as_string = true) {
		$root_dir = dirname(__DIR__);

		if (empty($this->version)) {
			$this->version["status"] = -1;

			if (PHP_OS === "Darwin") {
				$ttrss_version["version"] = "UNKNOWN (Unsupported, Darwin)";
			} else if (file_exists("$root_dir/version_static.txt")) {
				$this->version["version"] = trim(file_get_contents("$root_dir/version_static.txt")) . " (Unsupported)";
			} else if (is_dir("$root_dir/.git")) {
				$this->version = self::get_version_from_git($root_dir);

				if ($this->version["status"] != 0) {
					user_error("Unable to determine version: " . $this->version["version"], E_USER_WARNING);

					$this->version["version"] = "UNKNOWN (Unsupported, Git error)";
				}
			} else {
				$this->version["version"] = "UNKNOWN (Unsupported)";
			}
		}

		return $as_string ? $this->version["version"] : $this->version;
	}

	static function get_version_from_git(string $dir) {
		$descriptorspec = [
			1 => ["pipe", "w"], // STDOUT
			2 => ["pipe", "w"], // STDERR
		];

		$rv = [
			"status" => -1,
			"version" => "",
			"commit" => "",
			"timestamp" => 0,
		];

		$proc = proc_open("git --no-pager log --pretty=\"version-%ct-%h\" -n1 HEAD",
						$descriptorspec, $pipes, $dir);

		if (is_resource($proc)) {
			$stdout = trim(stream_get_contents($pipes[1]));
			$stderr = trim(stream_get_contents($pipes[2]));
			$status = proc_close($proc);

			$rv["status"] = $status;

			list($check, $timestamp, $commit) = explode("-", $stdout);

			if ($check == "version") {

				$rv["version"] = strftime("%y.%m", (int)$timestamp) . "-$commit";
				$rv["commit"] = $commit;
				$rv["timestamp"] = $timestamp;

				// proc_close() may return -1 even if command completed successfully
				// so if it looks like we got valid data, we ignore it

				if ($rv["status"] == -1)
					$rv["status"] = 0;

			} else {
				$rv["version"] = T_sprintf("Git error [RC=%d]: %s", $status, $stderr);
			}
		}

		return $rv;
	}

	static function get_schema_version(bool $nocache = false) {
		return self::get_instance()->_schema_version($nocache);
	}

	function _schema_version(bool $nocache = false) {
		if (empty($this->schema_version) || $nocache) {
			$row = Db::pdo()->query("SELECT schema_version FROM ttrss_version")->fetch();

			$this->schema_version = (int) $row["schema_version"];
		}

		return $this->schema_version;
	}

	static function cast_to(string $value, int $type_hint) {
		switch ($type_hint) {
			case self::T_BOOL:
				return sql_bool_to_bool($value);
			case self::T_INT:
				return (int) $value;
			default:
				return $value;
		}
	}

	private function _get(string $param) {
		list ($value, $type_hint) = $this->params[$param];

		return $this->cast_to($value, $type_hint);
	}

	private function _add(string $param, string $default, int $type_hint) {
		$override = getenv($this::_ENVVAR_PREFIX . $param);

		$this->params[$param] = [ self::cast_to(!empty($override) ? $override : $default, $type_hint), $type_hint ];
	}

	static function add(string $param, string $default, int $type_hint = Config::T_STRING) {
		$instance = self::get_instance();

		return $instance->_add($param, $default, $type_hint);
	}

	static function get(string $param) {
		$instance = self::get_instance();

		return $instance->_get($param);
	}

	/** this returns Config::SELF_URL_PATH sans trailing slash */
	static function get_self_url() : string {
		$self_url_path = self::get(Config::SELF_URL_PATH);

		if (substr($self_url_path, -1) === "/") {
			return substr($self_url_path, 0, -1);
		} else {
			return $self_url_path;
		}
	}

	static function is_server_https() : bool {
		return (!empty($_SERVER['HTTPS']) && ($_SERVER['HTTPS'] != 'off')) ||
			(!empty($_SERVER['HTTP_X_FORWARDED_PROTO']) && $_SERVER['HTTP_X_FORWARDED_PROTO'] == 'https');
	}

	/** generates reference self_url_path (no trailing slash) */
	static function make_self_url() : string {
		$proto = self::is_server_https() ? 'https' : 'http';
		$self_url_path = $proto . '://' . $_SERVER["HTTP_HOST"] . $_SERVER["REQUEST_URI"];

		$self_url_path = preg_replace("/\w+\.php$/", "", $self_url_path);

		if (substr($self_url_path, -1) === "/") {
			return substr($self_url_path, 0, -1);
		} else {
			return $self_url_path;
		}
	}

	/* sanity check stuff */

	private static function check_mysql_tables() {
		$pdo = Db::pdo();

		$sth = $pdo->prepare("SELECT engine, table_name FROM information_schema.tables WHERE
				table_schema = ? AND table_name LIKE 'ttrss_%' AND engine != 'InnoDB'");
		$sth->execute([self::get(Config::DB_NAME)]);

		$bad_tables = [];

		while ($line = $sth->fetch()) {
			array_push($bad_tables, $line);
		}

		return $bad_tables;
	}

	static function sanity_check() {

		/*
			we don't actually need the DB object right now but some checks below might use ORM which won't be initialized
			because it is set up in the Db constructor, which is why it's a good idea to invoke it as early as possible

			it is a bit of a hack, maybe ORM should be initialized somewhere else (functions.php?)
		*/

		$pdo = Db::pdo();

		$errors = array();

		if (strpos(self::get(Config::PLUGINS), "auth_") === false) {
			array_push($errors, "Please enable at least one authentication module via PLUGINS");
		}

		if (function_exists('posix_getuid') && posix_getuid() == 0) {
			array_push($errors, "Please don't run this script as root.");
		}

		if (version_compare(PHP_VERSION, '7.1.0', '<')) {
			array_push($errors, "PHP version 7.1.0 or newer required. You're using " . PHP_VERSION . ".");
		}

		if (!class_exists("UConverter")) {
			array_push($errors, "PHP UConverter class is missing, it's provided by the Internationalization (intl) module.");
		}

		if (!is_writable(self::get(Config::CACHE_DIR) . "/images")) {
			array_push($errors, "Image cache is not writable (chmod -R 777 ".self::get(Config::CACHE_DIR)."/images)");
		}

		if (!is_writable(self::get(Config::CACHE_DIR) . "/upload")) {
			array_push($errors, "Upload cache is not writable (chmod -R 777 ".self::get(Config::CACHE_DIR)."/upload)");
		}

		if (!is_writable(self::get(Config::CACHE_DIR) . "/export")) {
			array_push($errors, "Data export cache is not writable (chmod -R 777 ".self::get(Config::CACHE_DIR)."/export)");
		}

		if (self::get(Config::SINGLE_USER_MODE) && class_exists("PDO")) {
			if (UserHelper::get_login_by_id(1) != "admin") {
				array_push($errors, "SINGLE_USER_MODE is enabled but default admin account (ID: 1) is not found.");
			}
		}

		if (php_sapi_name() != "cli") {
			$ref_self_url_path = self::make_self_url();

			if ($ref_self_url_path) {
				$ref_self_url_path = preg_replace("/\w+\.php$/", "", $ref_self_url_path);
			}

			if (self::get_self_url() == "http://example.org/tt-rss") {
				$hint = $ref_self_url_path ? "(possible value: <b>$ref_self_url_path</b>)" : "";
				array_push($errors,
						"Please set SELF_URL_PATH to the correct value for your server: $hint");
			}

			if (self::get_self_url() != $ref_self_url_path) {
				array_push($errors,
					"Please set SELF_URL_PATH to the correct value detected for your server: <b>$ref_self_url_path</b> (you're using: <b>" . self::get_self_url() . "</b>)");
			}
		}

		if (!is_writable(self::get(Config::ICONS_DIR))) {
			array_push($errors, "ICONS_DIR defined in config.php is not writable (chmod -R 777 ".self::get(Config::ICONS_DIR).").\n");
		}

		if (!is_writable(self::get(Config::LOCK_DIRECTORY))) {
			array_push($errors, "LOCK_DIRECTORY is not writable (chmod -R 777 ".self::get(Config::LOCK_DIRECTORY).").\n");
		}

		if (!function_exists("curl_init") && !ini_get("allow_url_fopen")) {
			array_push($errors, "PHP configuration option allow_url_fopen is disabled, and CURL functions are not present. Either enable allow_url_fopen or install PHP extension for CURL.");
		}

		if (!function_exists("json_encode")) {
			array_push($errors, "PHP support for JSON is required, but was not found.");
		}

		if (!class_exists("PDO")) {
			array_push($errors, "PHP support for PDO is required but was not found.");
		}

		if (!function_exists("mb_strlen")) {
			array_push($errors, "PHP support for mbstring functions is required but was not found.");
		}

		if (!function_exists("hash")) {
			array_push($errors, "PHP support for hash() function is required but was not found.");
		}

		if (ini_get("safe_mode")) {
			array_push($errors, "PHP safe mode setting is obsolete and not supported by tt-rss.");
		}

		if (!function_exists("mime_content_type")) {
			array_push($errors, "PHP function mime_content_type() is missing, try enabling fileinfo module.");
		}

		if (!class_exists("DOMDocument")) {
			array_push($errors, "PHP support for DOMDocument is required, but was not found.");
		}

		if (self::get(Config::DB_TYPE) == "mysql") {
			$bad_tables = self::check_mysql_tables();

			if (count($bad_tables) > 0) {
				$bad_tables_fmt = [];

				foreach ($bad_tables as $bt) {
					array_push($bad_tables_fmt, sprintf("%s (%s)", $bt['table_name'], $bt['engine']));
				}

				$msg = "<p>The following tables use an unsupported MySQL engine: <b>" .
					implode(", ", $bad_tables_fmt) . "</b>.</p>";

				$msg .= "<p>The only supported engine on MySQL is InnoDB. MyISAM lacks functionality to run
					tt-rss.
					Please backup your data (via OPML) and re-import the schema before continuing.</p>
					<p><b>WARNING: importing the schema would mean LOSS OF ALL YOUR DATA.</b></p>";


				array_push($errors, $msg);
			}
		}

		if (count($errors) > 0 && php_sapi_name() != "cli") { ?>
			<!DOCTYPE html>
			<html>
				<head>
					<title>Startup failed</title>
					<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
					<link rel="stylesheet" type="text/css" href="themes/light.css">
				</head>
				<body class="sanity_failed flat ttrss_utility">
					<div class="content">
						<h1>Startup failed</h1>

						<p>Please fix errors indicated by the following messages:</p>

						<?php foreach ($errors as $error) { echo self::format_error($error); } ?>

						<p>You might want to check tt-rss <a target="_blank" href="https://tt-rss.org/wiki.php">wiki</a> or the
							<a target="_blank" href="https://community.tt-rss.org/">forums</a> for more information. Please search the forums before creating new topic
							for your question.</p>
					</div>
				</body>
			</html>

		<?php
			die;
		} else if (count($errors) > 0) {
			echo "Please fix errors indicated by the following messages:\n\n";

			foreach ($errors as $error) {
				echo " * " . strip_tags($error)."\n";
			}

			echo "\nYou might want to check tt-rss wiki or the forums for more information.\n";
			echo "Please search the forums before creating new topic for your question.\n";

			exit(1);
		}
	}

	private static function format_error($msg) {
		return "<div class=\"alert alert-danger\">$msg</div>";
	}
}